使用gtsummary中的tbl_continuous时如何获得均值和sd统计数据而不是中位数和iqr

我正在使用gtsummary号套餐.为了获得交叉的‘desg’和‘group’变量的描述性结果，我使用了tbl_continuous函数.

我得到了"中位数"和"IQR"作为结果衡量标准，但我想要的是mean和sd，正如我想要的.

library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
library(gtsummary)

# Sample data
data <- data.frame(
  desg = c('a', 'b', 'c', 'a', 'b', 'c'),
  group = c('before', 'before', 'before', 'after', 'after', 'after'),
  values = c(10, 15, 12, 18, 22, 20)
)

data %>%
  select(desg, group, values) %>%
  tbl_continuous(variable = values, by = group) %>%
  modify_spanning_header(all_stat_cols() ~ "**Treatment Assignment**")
Characteristic  Treatment Assignment
after, N = 31   before, N = 31
desg        
    a   18.0 (18.0, 18.0)   10.0 (10.0, 10.0)
    b   22.0 (22.0, 22.0)   15.0 (15.0, 15.0)
    c   20.0 (20.0, 20.0)   12.0 (12.0, 12.0)
1 values: Median (IQR)
Created on 2023-10-07 with reprex v2.0.2